Recently, the demand for information apparatuses with an imaging function, such as digital still cameras, digital video cameras, portable phones such as smartphones, and PDAs (Personal Digital Assistants) increases suddenly with the increase in resolution of solid-state imaging devices such as CDD (Charge Coupled Device) image sensors or CMOS (Complementary Metal Oxide Semiconductor) image sensors. Incidentally, each information apparatus having the aforementioned imaging function is referred to as imaging apparatus.
In these imaging apparatuses, a contrast AF (Auto Focus) system or a phase difference AF system has been used as a focus control method for focusing on a main photographic subject. Imaging apparatuses using both the phase difference AF system and the contrast AF system have been also proposed so far (for example, Patent Literatures 1 to 4).
Patent Literature 1 describes an imaging apparatus which selects to perform contrast AF or to perform contrast AF and phase difference AF in combination in accordance with whether to use electronic zoom or not.
Patent Literature 2 describes an imaging apparatus which selects to perform contrast AF or to perform phase difference AF in accordance with the kind of a lens to be mounted and the contrast of a photographic subject.
Patent Literature 3 describes an imaging apparatus which selects to perform contrast AF or to perform phase difference AF in accordance with the frequency of a photographic subject.
Patent Literature 4 describes an imaging apparatus which selects to perform contrast AF or to perform phase difference AF in accordance with an exposure condition.